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71.
72.
<正>最近,中国石油化工股份有限公司与德国巴斯夫集团在广东省茂名高新技术产业开发区为双方合资的世界级异壬醇装置建设工程举行奠基仪式。该装置为国内首个异壬醇生产装置,将于2015年投产,隶属于双方以50∶50比例建立的合资企业——茂名石化巴斯夫有限公司,满足市场对新一代增塑剂不断增长的需求。异壬醇是生产新一代增塑剂的原料,主要用于生产邻苯二甲酸二异壬酯(DINP)和非邻苯二甲酸酯Hexamoll誖DINCH誖等新一代 相似文献
73.
In situ time-series measurements of spectral diffuse downwelling irradiance from the Bermuda Testbed Mooring are presented. Averaged diffuse attenuation coefficients of downwelling irradiance, Kd,and their elastic and inelastic components are investigated at seven wavelengths. At shorter wavelengths (<510 nm), Kd is weakly dependent on the solar zenith angle owing to the prevailing scattering effect and therefore can be considered a quasi-inherent optical property. At longer wavelengths (>510 nm), Kd shows a strong dependence on the solar zenith angle. As depth increases, inelastic scattering plays a greater role for the underwater light field at red wavelengths. 相似文献
74.
Hai-Ping Cheng Lin-Lin Wang Mao-Hua Du Chao Cao Ying-Xia Wan Yao He Krishna Muralidharan Grace Greenlee Andrew Kolchin 《Journal of Computer-Aided Materials Design》2006,13(1-3):161-183
Over the past 6 years, we have engaged in a multi-faceted computational investigation of water–silica interactions at the fundamental physical and chemical level. This effort has necessitated development and implementation of simulation methods including high-accuracy quantum mechanical approaches, classical molecular dynamics, finite element techniques, and multi-scale modeling. We have found that water and silica can interact via either hydration or hydroxylation. Depending on physical conditions, the former process can be weak ( < 0.2 eV) or strong (near 1.0 eV). Compared to hydration, the latter process yields much larger energy gains (2–3 eV/water). Some hydroxylated silica systems can accept more water molecules and undergo further hydroxylation. We have also studied the role of external stress, effects of finite silica system size, different numbers of water molecules, and temperature dependences. 相似文献
75.
Studied the role of affect as a mediator of the overjustification effect and proposed that negative affect has a critical detrimental influence on intrinsic motivation, either as a reaction derived from self-perception and evaluation processes or as a factor that acts independently of these cognitive activities. Two studies, with 180 undergraduates, used the typical overjustification paradigm to test these hypotheses. In Exp I, the overjustification effect was successfully replicated for both behavioral and self-report measures of intrinsic motivation. It is important that the negative affect paralleled these results and was greatest in those conditions in which intrinsic motivation was predicted and found to be low (e.g., expected reward). In Exp II, affect was directly manipulated, independently of the cognitive manipulations. Results show that the induced positive affect erased the decrease in intrinsic motivation that was observed in Exp I. It is suggested that what determines the decrease in intrinsic interest in any activity is, in part, the amount of negative affect that becomes associated with the activity. (55 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
EP Nacheva CD Grace M Bittner DH Ledbetter RB Jenkins AR Green 《Canadian Metallurgical Quarterly》1998,100(2):93-105
A comparative analysis of the differentiation pattern, the proliferative behaviour, and the level of apoptosis between human benign and malignant neoplasms of smooth-muscle (SM) tissue is lacking. The clinical, histopathological, immunochemical, and immunocytochemical features of leiomyomas (LM) and leiomyosarcomas (LMS) were investigated by a panel of monoclonal antibodies specific for some differentiation markers of SM tissue (SM myosin and alpha-actin, desmin, and SM22) and for markers of non-muscle tissue (vimentin and non-muscle myosin). Proliferating normal and neoplastic cells were identified by proliferating-cell nuclear antigen (PCNA)/Ki67 immunostainings and the apoptotic cells were revealed by means of the terminal-deoxynucleotidyltransferase-mediated dUTP nick-end labelling technique. Gel electrophoresis and Western blotting, performed with anti-(SM1/SM2 myosin isoform) antibody, indicated quantitative differences between LMS and LM, which mirrored higher positive to negative nuclear ratios for PCNA, Ki67 and apoptosis in malignant as opposed to benign neoplasms. With LM, however, a similar SM1 to SM2 ratio could be associated with different proliferation levels. Uterine, gastric and intestinal LMS displayed specific patterns of SM1/SM2 and/or non-muscle myosin expression that were not paralleled by different levels of proliferation/apoptosis. While the level of PCNA/Ki67 correlated with the level of apoptosis in normal SM tissues and LM, that of LMS did not. In vivo at the cellular level, LM and uterine LMS displayed a near-uniform SM tissue differentiation, whereas the other LMS displayed a lesser or a heterogeneous immunoreactivity. In vitro, cultured LMS cells showed a limited and peculiar expression of SM myosin. In conclusion, there is no reciprocal relationship between degree of differentiation and the level of proliferation, as exemplified by the finding that the less differentiated intestinal LMS displays the lowest proliferative behaviour and that the relatively more differentiated gastric LMS/metastasis is more proliferative. 相似文献
77.
Compared the exposure model and the self-efficacy model by randomly assigning 32 18–76 yr old individuals with driving or height phobias to 1 of the treatment conditions or to a control condition. Results show that treatments were equivalent in duration of exposure and in degree of inducement to confront threats rapidly, but the self-efficacy (mastery) model was significantly more effective than exposure in restoring Ss' behavioral functioning and diminishing their anticipated anxiety and performance-related anxiety. Both treatments were more effective than the control condition. It is suggested that self-efficacy predicted therapeutic behavior change significantly better than did anxiety, exposure duration, or performance level achieved during treatment. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
79.
Green Bonnie L.; Grace Mary C.; Lindy Jacob D.; Titchener James L.; Lindy Joanne G. 《Canadian Metallurgical Quarterly》1983,51(4):573
117 individuals (mean age 37.77 yrs) who were at the fire and 30 individuals (mean age 40.72 yrs) who were not at the fire (bereaved families and rescue workers) were assessed regarding objective stressfulness of their fire experience, subjective stressfulness, and intensity of psychological symptoms (the Psychiatric Evaluation Form, PEF) in a structured clinical interview approximately 1 yr after the fire. Ss also filled out the Symptom Checklist-90, Revised Version (SCL-90R). 88 Ss were followed-up at 2 yrs. The group as a whole was more impaired than comparison samples of normals but less impaired than outpatients. Ss at the fire were less impaired than those not at the fire, who were similar to outpatients on the PEF. The latter group improved significantly on several measures from 1 to 2 yrs postfire, whereas the group at the fire showed little change. Results are discussed in the context of the specific instruments and methodology used in the present study, impairment levels of other samples, and the nature of the particular disaster. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
A simple empirical model is developed based on two-dimensional linearized Rayleigh-Taylor stability theory to describe the break-up of drops and bubbles in stagnant fluids. Splitting is predicted to occur if the growth of indentations on the leading edge is rapid enough relative to the rate at which the disturbance is carried around the interface to the equator. Experimental data on maximum stable sizes of drops and bubbles in viscous liquids are presented for eighteen different systems, covering a range much larger than in previous studies. Agreement between the model and experimental results is favourable. 相似文献